The present invention relates to an image forming apparatus such as an electrophotographic machine.
In general, toner is supplied to the surface of a photoconductive member of an electrophotographic machine when an electrostatic latent image is developed. Thereafter, a toner image is transferred to a paper sheet by a transfer process. However, some toner particles are left on the photoconductive member, and the surface of the photoconductive member is contaminated by the residual toner particles. In order to eliminate this drawback, a cleaning blade is brought into slidable contact with the surface of the photoconductive member to scrape the residual toner particles therefrom. However, when the surface of the photoconductive member is pressed by the cleaning blade for a long period of time or is heated upon motion of the cleaning blade, the surface shape and characteristics of the photoconductive member change, (i.e., so-called "pitting" occurs). In order to avoid this, the cleaning blade is brought into slidable contact with the photoconductive member to remove the residual toner particles in the copying mode, and is separated from the surface of the photoconductive member in the non-copying mode. In this manner, every time the cleaning blade is brought into contact with and separated from the surface of the photoconductive member in the copying mode and non-copying mode, the residual toner particles are removed, and are sent flying to the back of the cleaning blade and become attached thereto. Alternatively, developing medium carriers are inserted between the cleaning blade and the photoconductive member. As a result, a black stripe occurs in a copied sheet, and the surface of the photoconductive member is damaged.